I really need some help with this, forgot how to do it, THX!!!

Answer
The answer is 49 degrees
Explanation
The exterior angle, the angle outside the triangle, it going to equal the angles inside the triangles.
w-19+w=w+30 Combine like term so combine the w's to be 2w
2w-19=w+30 Add 19 to both sides 30+19=49
2w=w+49 Subtract w from both sides 2w-w=w
w=49
To check your work you can plug 49 into w and you get that the angles inside the triangle is 79 and the exterior angle is 79 when you plug back in 79 and 79=79